Mold Action Guide after Flooding: Ineffective Mold Products and Ineffective Black Mold Cleanup Procedures to Avoid
InspectAPedia® -
Warnings about ineffective mold removal systems & products
Warnings about bogus mold-detection methods used in buildings
How to save money on mold testing by avoiding unreliable mold tests and methods
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This chapter lists some ineffective or even possibly harmful procedures and products that are marketed to
"kill mold" or "prevent mold" - things that you should avoid any time, including when cleaning a building after it has been flooded. Our photograph shows an extensive toxic black mold reservoir in a New York City high rise apartment. Sprays, fogging, or ozone would be ineffective remedies for this problem.
If your building has been flooded, this website provides an easy to understand guide for flood damage assessment, setting
priorities of action, safety, and we provide special information about
avoiding or minimizing mold damage.
Our Flood Response Checklist lists key actions you should take after building flooding to minimize mold damage, and includes some safety warnings. We also list after-flood "anti-mold" procedures that do not work or are unsafe - to help you avoid unnecessary expense in dealing with mold
after a building flood.
If your building is already moldy or if you suspect mold related illness in your building, we link to a step by step Mold Action Guide dealing with toxic or allergenic indoor mold and other indoor contaminants:
when and how to inspect or test for mold, when to hire an expert, how to clean up a moldy area, when and how to perform post-remediation mold testing.
If your septic system has been flooded we link to an article outlining what to do about that system as well. Extensive, technically detailed in-depth articles on other mold detection, testing, and prevention methods are organized at our Mold Information Center
INEFFECTIVE PRODUCTS or Unreliable Products and Procedures Sold for Removing Mold, Cleaning Off Mold, or for Preventing Mold Growth
Disinfectants, mold biocides, mold killing sprays, mold washes, & fungicides: Spraying cleaners, disinfectants, bleach, fungicides can be used to clean a moldy surface if you wish, and where bacterial contamination is present or suspected they are appropriate. But do not use sprays or disinfectants without first drying the building and removing sludge, debris, and contaminated or moldy materials and then physically leaning all surfaces.
Use of disinfectants or biocides as part of
cleaning are appropriate at times, especially where there has been or may have been sewage backup where bacterial contamination is present. But no spray or gas is an effective substitute for
physically cleaning and physically removing mold and moldy materials. Watch out for companies who offer sprays or gases as a shortcut when cleaning is what's needed. A dead mold spore can still be toxic or allergenic. Clean off the mold from hard surfaces, and throw away moldy materials that cannot be cleaned.
Ozone for mold: Using ozone generators to "kill" mold. See Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous.
Dehumidification without Demolition Water "extraction" methods which simply run dehumidifiers in a building which has been flooded. we have found soaking wet wall cavities and insulation
many weeks after a building appeared "dry" when this method was used.
Blown-air Wall Cavity Treatments: "Water extraction" methods that cut small holes between wall studs to blow air through the wall cavity. In many buildings which we have investigated where
this method was used, we found severe mold growth on the cavity side of drywall and wallboard afterwards.
Water Detection to Track Moldy Areas: Use of moisture meters or infra red or other measures to "find the wet areas" - this works to find mold-risk areas only if
the cavities are still wet. In other words, if a building was wet in the past but has since dried, it could have a severe hidden mold infection that
will not be detected by using moisture-detection methods.
INEFFECTIVE METHODS Used to Detect Mold in buildings
Air sampling to screen buildings for mold: is useful but unreliable. We have documented very high variation in the level of airborne particles in buildings over very short time intervals, as little as over a few seconds. We have documented very high variation in the level of airborne particles in buildings depending also on how and exactly where the sample is collected, and depending on changes in building conditions.
Opening a basement door, turning on a fan, moving the air sampler from the floor to a table, can produce completely different results. Furthermore, even if we do detect evidence of problem mold in an air sample we do not know where it's coming from, how big the mold reservoir is, what caused it, or what level of cleanup is needed.
Is the mold just from a single pool table in the basement? Or is all of that clean-looking insulation mold contaminated. Air sampling is a useful tool but not a reliable building screen for mold when used alone and without a very thorough visual inspection and application of good building science.
Thermal scans and infra-red devices to find mold in buildings: the use of IR or thermography is effective in finding places where building temperature varies for any reason: missing insulation, wet insulation, electrical failures, radiant heat system failures.
IR and thermography are wonderful tools. But these tools can only detect a building condition that is present at the time that the tool is used. As with our moisture detection schemes above, if a building wall was flooded and its insulation soaked last year, the wall cavity may be mold-contaminated, but having since dried, the thermal scan method will not detect that condition.
MVOC-detection, mold related volatile organic compounds to find mold in buildings: are limited in effectiveness. As we discuss below at mold-sniffing dogs, not all molds produce MVOCs and MVOCs are also not produced consistently even when the mold species can make these gases. See Sampling for gases for details about MVOC detection.
Mold sniffing dogs used to find mold in buildings: are not a joke to everyone. Some mold investigators use dogs trained to respond to mold odors - usually gases produced by MVOC's. There are some fatal limitations to mold sniffing dogs that prevent an expert from taking them seriously, even if the dogs may be the cutest and most fun mold detection device around.
Spores or MVOCs may be absent: Allergenic or toxic molds may be present but may not be producing MVOCs or other materials that the dog senses. Not all molds produce gases and smells; even if a mold species does produce detectable MVOCs the mold colony does not always actively do so. Spore release from a mold colony and gas production from mold varies widely over time as a function of changes in the building environment: moisture, temperature, light exposure, air movement and other factors can "turn on" or "turn off" these effects. So our cute beagle mold sniffer may not sense a problem even though one is present.
Most mold sniffing dogs can't write a remediation plan. Even if a mold sniffer dog does suspect a mold problem in a building and tells his handler of it, that's not enough data to act upon. We do not know the size, location, or cause of the mold contamination; we do not know if the mold our molddog found was the only or even the most important mold reservoir.
Most mold sniffing dogs are short: not many of them can poke their noses in all of the areas where mold problems are most likely such as high on building walls, along building ceilings, across attic insulation, etc. People who describe the mold sniffing dog service to us have all confirmed that not once did the mold detection dog's handler pick up the dog and lift it into the air so that the dog could thoroughly explore all of the building's ceilings, nor did these critters crawl through attic insulation.
Mold sniffing may be hazardous to the dog's health. We have been collecting data for two decades showing that some pets become sensitized to and very ill from exposure to some molds. Some of them have died. It's not good for the dog to keep going into moldy buildings - and if the dog wore a dog-fitted HEPA respirator it's doubtful s/he would smell building conditions very accurately.
Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
Additional technical contributors & reference sources for this article are listed below.
Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. (727) 595-4211 mark@BestTampaInspector.com 11/06
Hankey and Brown home inspectors, Eden Prairie, MN, technical review by Roger Hankey, prior chairman, Standards Committee, American Society of Home Inspectors - ASHI. 952 829-0044 - hankeyandbrown.com 11/06
Arlene Puentes, a licensed home inspector, educator, and building failures researcher in Kingston, NY. 11/29/06
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Kansas State University, department of plant pathology, extension plant pathology web page on wheat rust fungus: see http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp
"A Brief Guide to Mold, Moisture, and Your Home",
U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
US EPA - Mold Remediation in Schools and Commercial Building [Copy on file at /sickhouse/EPA_Mold_Remediation_in_Schools.pdf ] - US EPA
US EPA - Una Breva Guia a Moho - Hongo [Copy on file as /sickhouse/EPA_Moho_Guia_sp.pdf - en Espanol
Allergies, Allergens, Allergy Testing in buildings - References & Products
Allergen Tests in buildings advice about how to test, what to look for, in evaluating the level of dog, cat, or other animal allergens in a building
"IgG Food Allergy Testing by ELISA/EIA, What do they really tell us?" Sheryl B. Miller, MT (ASCP), PhD, Clinical Laboratory Director, Bastyr University Natural Health Clinic - ELISA testing accuracy: Here is an example of Miller's critique of ELISA
http://www.betterhealthusa.com/public/282.cfm - Townsend Letter for Doctors and Patients
The critique included in that article raises compelling questions about IgG testing assays, which prompts our interest in actually screening for the presence of high levels of particles that could carry allergens - dog dander or cat dander in the case at hand.
http://www.tldp.com/issue/174/IgG%20Food%20Allergy.html contains similar criticism in another venue but interestingly by the same author, Sheryl Miller. Sheryl Miller, MT (ASCP), PhD, is an Immunologist and Associate Professor of Basic and Medical Sciences at Bastyr University in Bothell, Washington. She is also the Laboratory Director of the Bastyr Natural Health Clinic Laboratory.
Allergens: Testing for the level of exposure to animal allergens is discussed at http://www.animalhealthchannel.com/animalallergy/diagnosis.shtml (lab animal exposure study is interesting because it involves a higher exposure level in some cases
Allergens: WebMD discusses allergy tests for humans at webmd.com/allergies/allergy-tests
Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice
Rodent control issues, including dander, fecal, and urine contamination of buildings and Building insulation are discussed at our
Associations: Sick House, Sick Building, SBS - Air Quality, Government, Private Associations and Information Resources
Atlas of Clinical Fungi, 2nd Ed., GS deHoog, J Guarro, J Gene, & MJ Figueras, Centraalbureau voor Schimmelcultures, Universitat Rovira I Virgili, 2000, ISBN 90-70351-43-9 (you can buy this book at Amazon) - The Atlas of Clinical Fungi is also available on CD ROM
Atlas of Indoor Mold, Online Clinical Mold Atlas, Toxins, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)
Black Mold that is Harmless Photos of recognizable, usually harmless black mold on wood, bluestain, ceratocystis, ophistoma
Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination
Classes of Mold: what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully?
"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
"Disease Prevention Program for Certain Vegetable Crops," David B. Langston, Jr., Extension Plant Pathologist - Vegetables, University of Georgia (PDF document) original source: www.reeis.usda.gov/web/crisprojectpages/209797.html
"Disease Prevention in Home Vegetable Gardens,"
Patricia Donald,
Department of Plant Microbiology and Pathology,
Lewis Jett
Department of Horticulture, University of Missouri Extension - extension.missouri.edu/publications/DisplayPub.aspx?P=G6202
Fifth Kingdom, Bryce Kendrick, ISBN13: 9781585100224, is available from the InspectAPedia online bookstore - we recommend the CD-ROM version of this book. This 3rd/edition is a compact but comprehensive encyclopedia of all things mycological. Every aspect of the fungi, from aflatoxin to zppspores, with an accessible blend of verve and wit. The 24 chapters are filled with up-to-date information of classification, yeast, lichens, spore dispersal, allergies, ecology, genetics, plant pathology, predatory fungi, biological control, mutualistic symbioses with animals and plants, fungi as food, food spoilage and mycotoxins.
Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous.
Rot concerns in buildings-some building mold such as Meruliporia incrassata "Poria" risks serious rot and hidden structural damage
US EPA: Una Breva Guia a Moho - Hongo [Copy on file as /sickhouse/EPA_Moho_Guia_sp.pdf - en Espanol
OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold
Mold or allergens may not be the only or even the main indoor environmental contaminant. Don't let media attention to mold
cause so much enviro-scare fear that other, possibly more urgent hazards go un-addressed.
Ozone Warnings - Use of Ozone as a "mold"
remedy is ineffective and may be dangerous.
Pet control - if you can't say goodbye to your bird, cat, dog, guinea pig, hamster, tropical fish, then limit the
areas they occupy and limit the airflow from that area to sleeping or other areas of the building, use allergenic
bedding, eliminate wall-to-wall carpeting, improve housecleaning including use of a HEPA-rated vacuum cleaner. For more details
see our article Dog, Cat, and Other Animal Dander - Information for Asthmatics and Indoor Air Quality
Rodents, Mice, Squirrel Control - I find high levels of mouse and rodent dander, fecal dust, and urine-contaminated dust in some buildings,
and high levels of these materials in building insulation in those locations. If you have a mouse problem, particularly if mice and their waste (fecals or urine) are contaminating
the building HVAC or building insulation, may need both steps to clean up or remove infected materials and steps to stop an ongoing
rodent problem. If squirrels are a problem, the cleanup needs to include closing off entry openings into the building. Get some
help from a licensed pest control expert.
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